Photographic material having slippageimproving additive in surface coating

ABSTRACT

LIGHT SENSITIVE PHOTOGRAPHIC MATERIAL HAVING IN AT LEAST ONE OUTER LAYER, AS AN ANTI-FRICTION COMPONENT, A WATERINSOLUBLE COMPOUND OF THE FORMULA:   R1-O-CH2.CHOH-CH2-/-(R3-O)N-R2   WHEREIN R1 IS ALKYL (PREFERABLY STRAIGHT CHAIN) OF 8-24 CARBON ATOMS, OR ARYL; R2 IS ALKYL OF 8-24 CARBON ATOMS; R3 IS ALKYLENE OR PHENYLENE, AND N IS AN INTEGER FROM 0 TO 7.

"United States Patent Office 3,625,692 Patented Dec. 7, 1971 PHOTOGRAPHIC MATERlAL HAVING SLIPPAGE- IMPROVING ADDITIVE IN SURFACE COATING Karl-Otto Meyer, Leverkusen, and Wolfgang Himmelmann, Cologne-Stammheim, Germany, assignors to Agfa-Gevaert Aktiengesellschaft, Leverkusen, Germany No Drawing. Filed Oct. 24, 1968, Ser. No. 770,423

Int. Cl. G03c 1/16 US. CI. 96-67 3 Claims ABSTRACT OF THE DISCLOSURE Light sensitive photographic material having in at least one outer layer, as an anti-friction component, a waterinsoluble compound of the formula:

wherein R is alkyl (preferably straight chain) of '8-24 carbon atoms, or aryl; R is alkyl of 8-24 carbon atoms; R is alkylene or phenylene, and n is an integer from to 7.

The present invention relates to photographic material of improved slippage characteristics.

In the manufacture and use of certain photographic materials, problems of adhesion and friction frequently occur. In order to solve them satisfactorily, there are used lubricant coatings which may at the same time also have antistatic properties. Adhesion and friction play an important role in the case of all photosensitive materials in strip form when they are inserted in magazines or cassettes. Particular value must be placed on slippage characteristics in the case of motion picture and 8-mm. film. Here certain ranges of slippage characteristics are desirable, since too high a slippage is just as disadvantageous as too low a slippage.

Lack of movement of the projected picture on the screen is dependent on this optimum adjustment.

For controlling the slippage characteristics of photographic materials, there can, of course, be used only compounds which, in addition to having the desired physical properties, are photographically inert. For these reasons, the known compounds are only of limited utility.

Known additions are, for instance, carnauba wax, beeswax, petroleum waxes, such as ozokerite, industrial waxes, paraffin oil, silicon oil, sodium stearate, finely divided graphite, talc, esters of monocarboxylic acids having a chain length of 14-20 C atoms, triglycerides, stearoyl aminobenzene sulfonic acids, alkyl methyl taurides having alkyl radicals of C -C acylated taurine, and B-dialkylamino-propionic acid. Many of these compounds do not satisfy the demanding requirements since they detrimental- 1y affect the photographic emulsions. Sodium stearate reacts with the gelatin and a dependable coating is not obtained. Furthermore, stearic acid changes the shades of the image dyes used in color photography. Other lubricants can easily be removed from the surface and sweat out of the emulsion. The effectiveness is then reduced and frequently even entirely reversed, since the compounds deposit in the projector aperture or cause sticking.

The slippage-improving additives are in general incorporated in the uppermost colloid emulsion, preferably in gelatin or other water-soluble binder. However, they can also be dissolved in organic solvents which neither dissolve nor swell the gelatin or the supports, and the solution can be applied to both surfaces. This applies in particular to coated photographic materials, such as, for instance, 8-mm. films. In another application, the compounds are dissolved in combination with water-insoluble polymers and the mixtures applied to the emulsion side and the rear side (as lacquers).

The object of the present invention is to develop new slippage agents for photographic materials which are photographically inert, can be applied by customary methods, and have a good slippage-improving action.

It has now been found that the slippage characteristics of photographic materials can be excellently increased by using as slippage-improving additives, water-insoluble ethers of the following formula:

R alkyl, preferably unbranched, with 8-24 C atoms, and especially with 8-18 C atoms; or aryl, particularly phenyl, which is preferably substituted with alkyl of 8-24 C atoms;

R =alkyl radicals having -8-24 C atoms, preferably unbranched, and preferably with 8-18 C atoms;

R 1) alkylene, preferably unbranched, with up to 6 C atoms, in which the alkylene chain may be substituted, preferably with hydroxyl-ethylene or propylene being preferred, for instance:

or (2) phenylene which can be substituted, for instance by short-chain aliphatic radicals with up to 3 C atoms;

n=0-7 preferably 1-6 when R is alkylene, and preferably 1 when R is phenylene.

The compounds to be used in accordance with the invention consist of molecules having intermediate hydrophilic parts and terminal hydrophobic parts. They are water-insoluble. The compounds can be applied in various ways. They can, for instance, be dissolved in sol-vents which are only slightly miscible if at all, in water, dispersed in an aqueous solution of a photographic emulsion colloid, preferably gelatin, with the addition of a wetting agent which can be used for photographic purposes. 'The mixture can then be applied, for instance, to the photosensitive emulsion as a protective coating or specifically with addition of dyestuffs, to the treated rear side of a film in the form of a non-curl layer.

In another application, the compounds which are to be used in accordance with the invention are dissolved in organic solvents and the latter applied directly onto one or both sides of the photographic material without a binder, and possibly with the addition of wetting agents. After the removal of the solvent, a thin film remains consisting merely of the compound itself. This method is used only occasionally in the case of uncoated material, since disturbances can occur upon application of the emulsion.

In another application, the compounds are dissolved with a water-insoluble film-forming polymer in an or ganic solvent, and this solution is applied to one or both sides of the photographic material.

The present compounds can be used especially easily, since, in contradistinction to most of the previously known slippage-increasing substances, they produce stable dispersions in water-soluble colloids such as gelatin. Parafiins can, for instance, be readily emulsified, but the dispersions foam slightly.

The compounds to be used in accordance with the invention are readily compatible with gelatin, since, due to their water-insolubility, they are inert with respect to the gelatin. Very uniform emulsions are obtained, and the viscosity of gelatin solutions is not increased by addition of the slippage aid.

Coatings of excellent slippage characteristics are obtained, in which connection it should be especially mentioned that by the addition of the compounds, the desired slippage characteristics can be adjusted in a simple and reproducible manner. This result can be obtained by a suitable selection of one of the agents to be used in accordance with the invention or by the concentration in the coating in question. The optimum quantity can be determined in simple manner by ordinary means.

The following compounds have proven to be particularly useful:

The above compounds are prepared by known methods, for instance by adding 242.4 g. of distilled dodecyloxypropylene oxide drop by drop into a mixture of 186.3 g. of n-dodecanol and 3 ml. of boron tri fluoride-ethyl ether adduct (48% B lat 30 C. with agitation. The reaction mixture is thereupon stirred for 1 hour at 65 C., 1 hour at 80 C., 1 hour at 100 "C. and 4 hours at 110 C. After again adding 0.5 ml. of BF adduct, the mixture is stirred for minutes with 200 ml. of water, and then neutralized with NaHCO solution and washed three times with 500 ml. of Water. The reaction product is dissolved in benzene and after drying over CaCl boiled for 10 minutes with activated carbon. After filtration, the solvent is removed in vacuo.

The present slippage agents can be used for the most varied kinds of photographic materials. They are particularly suitable for conventional materials which contain silver halide as the photosensitive substance. Their use is not limited to specific photographic materials, and equally good results are obtained both in the case of singleor multi-coated black-and-white or color photographic materials. In the same manner, the slippage agents can be used for every kind of photosensitive materials, including those which contain diazonium salts as photosensitive substances.

4 EXAMPLE 1 In 500 m1. of a 2.5% aqueous gelatin solution containing 10 m1. of a 4% aqueous saponin solution, there are emulsified, by vigorous agitation at room temperature, 10 and 20 ml. respectively of a 2.5% solution of glycerinl,3-didodecyl ether in CH Cl or CH CCl (corresponding to 2 and 4% slippage agent respectively, based on the dry weight of the gelatin), and the pH is adjusted to 6.2 with sodium hydroxide. After addition of a hardening agent, for instance 4 ml. of a 5% aqueous chromium acetate solution, this coating solution is applied to the silver halide-gelatin emulsion coating of a photographic black-and-white material and dried in the customary manner. The slippage agent coatings obtained are clear. The photographic properties are unaffected.

Measurement of the coefficient of sliding friction gave the following values:

2% glycerin-1,3-didodecyl ether 0.16 4% glycerin-1,3-didodecyl ether 0.14 Control without slippage agent 0.26

The critical value of the coefiicient of sliding friction which must not be exceeded is 0.20.

The application of the other compounds mentioned above is carried out in anagolous manner.

The lubricants are used in quantities of l to 10%, and preferably of 2 to 4%, based on the dry weight of the gelatin.

EXAMPLE 2 A multi-layer 8-mm. color film is treated, after coating, with a solution of mg. of glycerin-l-stearyl-3- dodecyl ether in 100 ml. of trichlor-ethane-l,1,l.

Measurement of the coefiicient of sliding friction gave the following values:

Untreated (control) 0.29 Treated 0.18

EXAMPLE 3 In a mixture of 400 ml. of acetone, 50 ml. of methyl glycol acetate, 25 ml. of ethanol and 25 ml. of n-butanol, there are dissolved 8 g. of cellulose acetate phthalate (CAP) or cellulose acetate butyrate (CAB) and then 0.8 g. of glycerin-1,3-didodecyl ether. The mixture is applied to the photosensitive silver halide emulsion coating of a photographic paper, and dried in the customary manner.

Measurement of the coefficient of sliding friction gave the following values:

C AP' alone 0.17 OAP-l-glycerin-1,3-didodecyl ether 0.13 CAB alone 0.15 CAB+glycerin-l,3-didodecyl ether 0.11 Control without slippage agent 0.17

The coefficients of sliding friction for paper coatings are generally lower than those of corresponding film coatings; the effectiveness of the slippage agents of the invention can be clearly observed from the measured values.

We claim:

1. Light-sensitive photographic material having at least one surface coating containing as a slippage-improving additive, a water-insoluble compound of the following for mula:

R is selected from the group consisting of alkyl groups of 8-24 C atoms;

6 R is an alkyl group of 8-24 C atoms; References Cited R is selected from the group consisting of alkylene and UNITED STATES PATENTS h l g d p my groups 3,514,293 5/1970 Knox 96114.5

n is an integer from 0 to 7.

2. Photosensitive material according to claim 1, Where- 5 in R is an unbranched alkyl group of 8-18 C atoms. WILLIAM A Pmllary Exammer 6. Photosensitive material according to claim 1, where- HUSACK, Asslstant EXamlIlel' in R is selected from the group consisting of ethylene,

2-hydroxy propylene, butylene and phenylene groups and CL mixtures thereof. 10 96-87 R, 94 R, 114.5 

